Do not check intersections or unions to ignore propegating reference flags, properly set comparing jsx flag

Author: weswigham

src/compiler/checker.ts

@@ -15363,12 +15363,12 @@ namespace ts {
             function isRelatedTo(originalSource: Type, originalTarget: Type, reportErrors = false, headMessage?: DiagnosticMessage, intersectionState = IntersectionState.None): Ternary {
                 // Before normalization: if `source` is type reference (ergo an object), and `target` is primitive,
                 // skip all the checks we don't need and just return `isSimpleTypeRelatedTo` result
-                if (getObjectFlags(originalSource) & ObjectFlags.Reference && originalTarget.flags & TypeFlags.Primitive) {
+                if (!(originalSource.flags & TypeFlags.UnionOrIntersection) && getObjectFlags(originalSource) & ObjectFlags.Reference && originalTarget.flags & TypeFlags.Primitive) {
                     if (isSimpleTypeRelatedTo(originalSource, originalTarget, relation, reportErrors ? reportError : undefined)) {
                         return Ternary.True;
                     }
                     else {
-                        reportErrorResults(originalSource, originalTarget, Ternary.False, /*isComparingJsxAttributes*/ true);
+                        reportErrorResults(originalSource, originalTarget, Ternary.False, !!(getObjectFlags(originalSource) & ObjectFlags.JsxAttributes));
                         return Ternary.False;
                     }
                 }